CONN 

S 

43 

.E22 

no.105 


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in  2011  with  funding  from 

LYRASIS  members  and  Sloan  Foundation 


http://www.archive.org/details/potatoscabproteiOOthax 


l-AoS'.V  'OS"  CosN 


O.  E.  S.  Library.  Cop.  2. 


43 


THE 


ConnBcticut  Agricultural  Exueriment 

NEW    HAVEN,    CONN. 
BULLETIN     No.     105 

DECEMBER.    1890. 


The  Bulletins  and  Reports  of  this  Station  are  mailed  free  to 
every  citizen  of  Connecticut  who  applies  for  them  seasonably. 


CONTENTS. 

Page 
Notice  as  to  supply  of  Station  Reports  for  1890  and  Bulletins  for 

1891, 2 

Corrections,     ........  2 

The  Potato  Scab,  .......  3 

The  Proteids  of  the  Oat-Kernel,       .....  5 

Milk  Testing,        .  .  .  .  .  .  .  .8 


Notice  as  to  Supply  of  Station  Reports. 

The  Annual  Report  of  this  Station  for  the  current  year,  to  be  printed 
at  State  expense,  is  limited  to  an  edition  of  7,000  copies.  After  reserving 
copies  for  exchanges  with  other  Experiment  Stations  and  Agricultural 
Journals,  the  remaining  Reports  will  be  sent  to  Citizens  of  Connecticut 
who  shall  apply  for  them  by  mail  during  the  next  two  months.  These 
copies  will  be  supplied  in  the  order  in  which  the  applications  are 
received  until  the  edition  is  exhausted,  and  if  the  demand  in  the  State 
continues  as  heretofore,  few  or  none  will  remain  for  distribution 
outside  of  Connecticut. 

Extra  copies  can.  however,  be  had  if  called  for  before  the  printing- 
forms  are  broken  up.  Such  copies  will  be  struck  off  and  supplied  early 
next  year  to  Citizens  of  other  States  who  apply  to  this  Station  before 
January  1st,  and  who  remit  25  cents  per  copy  to  defray  costs.  This 
remittance  will  also  secure  to  the  sender  a  copy  of  each  Bulletin  issued 
by  this  Station  during  next  year. 

Coin  may  be  forwarded  by  Post  at  sender's  risk  with  very  small 
chance  of  loss,  if  properly  mailed,  as  follows  :  Cut  an  inch  hole  near 
one  end  of  a  card  or  scrap  of  thin  paper-box  that  will  just  fit  inside  an 
envelope,  fasten  a  twenty-five  cent  piece  in  the  cavity  by  pasting  paper 
over  it  on  both  sides  of  the  card,  write  thereon  name  and  Post  office 
address,  inclose  within  an  envelope,  and  send  as  a  letter  prepaid  in 
full.     P.  O.  stamps  cannot  be  accepted. 

UEfT  A  copy  of  this  Bulletin  is  mailed  to  every  address  on  our  books, 
and  special  attention  is  called  to  the  necessity  of  making  new  and  early 
application  for  Reports  and  Bulletins,  as  on  December  1,  we  begin  to 
revise  our  General  Address  List  for  the  next  year  and  our  old  lists 
will  be  entirely  discarded  when  the  Annual  Report  and  the  next 
Bulletin  are  sent. 

HSf"  Our  Special  List  of  Exchanges  to  Agricultural  Colleges,  Experi- 
ment Stations  and  Journals  is  not  affected  by  this  revision. 

Corrections. 

The  per  cent,  of  soluble  phosphoric  acid  in  Lister's  Ammoniated 
Bone  Superphosphate  (No.  2823,  page  10,  Bulletin  104)  is  7.05  and  not 
1.05  as  printed. 

The  valuation  of  Crocker's  Ammoniated  Bone  Superphosphate  (No. 
2799,  page  13,  Bulletin  104)  is  $26.37  and  not  $36.37  as  printed. 


THE    POTATO    SCAB. 

By  Roland  Thaxter,  Mycologist. 

The  "  Potato  Scab "  has  been  under  investigation  in  the 
Mycological  Laboratory  of  this  Station  for  some  months  with 
results  of  considerable  interest.  While  heretofore  the  disease 
has  been  considered  to  be  an  effect  of  numerous  agencies,  especially 
chemical  or  physical,  and  more  recently  has  been  referred  to  the 
attack  of  a  specific  Bacterium,  it  is  shown,  by  experiments  at  this 
Station,  to  be  due  to  the  direct  action  of  a  very  peculiar  fila- 
mentous fungus  of  extremely  small  dimensions  which  has  been 
found  invariably  to  accompany  the  disease  wherever  it  has  been 
examined  by  the  writer  in  New  England. 

This  fungus  produces  an  evanescent  grey  film  in  connection 
with  the  disease,  generally  visible  without  a  lens,  especially  in  the 
earlier  stages  of  the  affection,  and  has  been  obtained  absolutely 
pure  for  experiment,  by  the  ordinary  methods  of  isolation  used 
in  bacteriology.  On  nearly  all  neutral  or  slightly  acid  substrata 
used  for  its  cultivation,  it  forms  a  compact  lichenoid  growth 
accompanied  by  a  peculiar  dark  stain  which  diffuses  from  it 
through  the  nutrient  substance.  Its  fructification  is  aerial  and 
consists  in  the  production  of  short  rod-like  bodies  and  spirals ; 
the  latter  terminal,  the  former  resulting  from  the  general 
segmentation  and  breaking  up  of  the  aerial  filaments  into  short 
pieces ;  the  general  mass,  which  is  bluish  grey  in  color,  closely 
resembling  various  forms  of  bacteria  in  shape  and  size,  the 
diameter  of  both  the  vegetative  and  reproductive  portions  of 
the  plant  reaching  only  from  five  to  eight  ten-thousandths 
of  a  milimeter,  on  the  average.  The  fungus,  which  except 
for  its  apparently  true-branching  and  aerial  fructification  re- 
sembles in  some  respects  certain  of  the  polymorphic  Bacteria, 
cannot  as  yet  be  referred  to  any  described  form  and  answers  to 
no  generic  description,  as  far  as  has  been  ascertained.  It  is 
readily  propagated  by  means  of  its  "  spores,"  as  well  as  by  the 
smallest  possible  portions  which  can  be  detached  from  its  vege- 
tative filaments.  When  transferred  from  pure  cultures  to  young 
growing  potato-tubers,  it  reproduces  the  disease  upon  them  with 
certainty  at  the  point  of  application,  under  rigid  experimental 
conditions. 


This  fact,  together  with  the  invariable  association  of  the  fungus 
with  the  disease  in  nature  (as  far  as  observed  by  the  writer)  after 
it  has  once  been  recognized  and  sought  for,  may  be  considered 
practically  indubitable  evidence  of  the  connection  between  the 
two  as  cause  and  effect.  Whether  the  disease  under  considera- 
tion is  identical  with  that  which,  as  previously  mentioned,  has 
been  referred  to  a  bacterial  origin  is  quite  another  matter,  and 
there  is  every  reason. to  believe  that  the  two  are  wholly  distinct 
affections  except  in  so  far  as  their  results  are  somewhat  similar. 
Further  than  this  nothing  can  be  said,  except  that  the  disease  here 
investigated  usually  takes  the  form  of  what  has  been  called  "  deep  " 
scab,  which  may  possibly  be  found  to  be  distinct  in  origin  from 
the  "  surface  "  scab  with  which  it  is  often  associated  even  in  New 
England. 

In  connection  with  this  subject  a  study  is  being  made  of  another 
organism  morphologically  identical  with  the  scab-fungus ;  but 
apparently  somewhat  different  physiologically.  This  organism, 
which  may  nevertheless  ultimately  prove  to  be  entirely  identical 
with  the  scab-fungus,  is  one  of  the  commonest  forms  of  growth 
upon  rubbish,  old  hay  or  straw,  barn-yard  manure  and  similar 
substances,  and  its  study  is  being  prosecuted  with  a  view  to 
ascertain  whether  this  identity,  if  it  can  be  shown  to  exist,  may 
not  furnish  a  rational  explanation  of  the  observed  fact  that  land 
containing  much  miscellaneous  rubbish,  or  fertilized  with  barn- 
yard manure,  is  generally  associated  with  scab  in  the  potatoes 
raised  upon  it. 

Having  occupied  so  short  a  time,  the  work  upon  this  disease 
has  been  of  necessity  preliminary  and  it  has  not  been  possible  to 
consider  experimentally,  the  practical  side  of  the  question  to  which 
attention  will  be  given  in  the  further  investigations  to  be  carried 
on  during  the  coming  season. 


THE   PROTEIDS   OK    ALBUMINOIDS   OF    THE 
OAT-KERNEL. 

By  Thomas  B.  Osborne,   Chemist. 

An  extended  study  of  the  Proteids  of  the  Oat-kernel  has  been 
carried  on  for  several  months  in  the  Chemical  Laboratory  of  the 
Station.     The  results  of  this  work  are  very  briefly  as  follows  : 

1.  The  proteid  body  removed  from  fresh-ground  oats  by  direct 
extraction  with  weak  alcohol,  first  observed  by  Norton  and  by 
him  designated  ghdin,  when  dehydrated  by  absolute  alcohol  and 
dried  over  sulphuric  acid  is  a  light  yellowish  powder,  insolu- 
ble in  water  as  well  as  in  absolute  alcohol,  soluble  in  mixtures  of 
alcohol  and  water,  soluble  also  in  dilute  acids  and  alkalies  and 
from  these  solutions  thrown  down  by  neutralization.  Separated 
from  its  solution  in  alcohol  of  60  percent,  by  evaporating  off  the 
alcohol,  it  forms  a  yellowish  slimy  mass.  Its  composition — the 
average  of  five  accordant  analyses,  representing  various  fractional 
precipitations  of  the  alcohol-extract — is  given  in  the  table,  p.  7, 
under  I.  This  substance  is  remarkable  for  its  considerable  con- 
tent of  sulphur,  which  is  exceeded  by  that  of  keratin  alone  among 
the  proteids  and  is  otherwise  equaled  only  by  that  recorded  in 
some  analyses  of  serum-albumin. 

2.  When  oats  are  treated  first  with  water  or  10-percent-solu- 
tion  of  common  salt,  before  extraction  with  dilute  alcohol,  the 
alcohol-soluble  proteid  undergoes  alteration  and  a  body  of  dif- 
ferent composition  and  properties  results.  In  the  table,  II  is  the 
mean  of  four  closely-agreeing  analyses  of  this  substance.  It  is 
much  more  soluble  in  dilute  alcohol  than  I,  and  when  wet  with 
absolute  alcohol,  the  moisture  attracted  from  the  air  shortly 
renders  it  gummy  and  tenaciously  adhesive,  unlike  I. 

Its  composition  as  regards  carbon,  hydrogen  and  nitrogen,  is 
very  near  to  that  found  by  Dumas  and  Cahours  and  also  by 
v.  Bibra,  for  plant- gelatin  (extracted  by  hot  alcohol  from  wheat- 
gluten  and  remaining  dissolved  in  the  alcohol  when  cold) — the 
substance  which  Taddei  first  prepared  from  wheat-gluten  and 
termed   gliadin.     Kreusler  obtained  this  material  from  the  oat, 


6 

but  what  Ritthausen  and  he  have  named  oat-gliadin,  is  a  product 
of  its  further  alteration  by  the  chemical  treatment  to  which  it 
was  subjected,  with  a  view  of  obtaining  from  the  oat  a  body  with 
18  percent,  of  nitrogen,  which  Ritthausen  was  led  to  regard  as 
characteristic  of  wheat-gliadin. 

3.  In  the  presence  of  water,  or  10-percent-salt-solution,  the  re- 
maining proteids  of  the  oat  rapidly  suffer  change  and  become 
insoluble  in  salt-solntion,  as  recognized  by  Weyl. 

4.  The  proteid  extracted  by  10-percent-salt-solution,  behaves 
tpwarcls  reagents  like  the  myosin-globulin  from  animal  muscle  as 
first  stated  by  Weyl.  Contrary  to  Weyl's  observations,  however, 
the  coagulation-temperature  (80°-100°)  is  much  higher  than  that 
of  animal  myosin  (55°-60°).  This  proteid  appears  to  be  the  result 
of  alteration  similar  to  that  by  which  myosin  is  formed  from 
myosinogen.  In  composition  it  is  quite  close  to  muscle-myosin, 
as  seen  from  analysis  IV.  The  greatest  proportion  of  this  proteid 
extracted  by  salt-solution  from  the  oat  was  1.3  percent. 

5.  The  proteid  extracted,  after  complete  exhaustion  of  the  oats 
with  .alcohol  of  0.9  sp.  gr.,  by  dilute  potash,  analysis  V,  as  well 
as  that  dissolved  out  by  10-percent. -salt-solution,  analysis  Va,  has 
very  nearly  the  same  composition  as  the  proteid  extracted  by 
salt-solution  directly. 

6.  A  large  share  of  the  proteids  of  the  oat,  when  exposed  to 
the  action  of  water,  becomes  insoluble  in  dilute  potash-solution, 
the  amount  so  rendered  insoluble  increasing  with  the  duration  of 
the  contact  with  water.  One  hour's  treatment  with  water  ren- 
dered one-half,  24  hours'  treatment  made  two-thirds  insoluble  in 
^--percent-solution  of  potash.  The  composition  of  the  part 
soluble  in  potash,  after  action  of  water  (and  removal  of  the  alco- 
hol-soluble proteid),  is  the  same  as  that  of  the  part  soluble  in  salt- 
solution.  Analysis  VI.  This  proteid,  obtained  by  extraction 
with  potash,  after  the  action  of  water,  is  probably  the  substance 
called  by  Kreusler  Oat-Legumin.  To  obtain  the  solution  from 
which  his  oat-legumin  was  prepared,  Kreusler  mixed  1^  lbs.  of 
ground  oats  with  5  liters  of  water  and  added  3  gm.  of  potash  to 
neutralize  the  acid  of  the  oats 

7.  When  ground  oats  are  directly  extracted  by  weak  potash- 
solution  without  previous  treatment  with  water,  nearly  the  whole 
of  the  proteids  is  dissolved.  The  substance  so  extracted,  after 
completely  removing  the  body  soluble  in  weak  alcohol,  has  a 
different   composition    from   that    similarly    obtained    after    first 


treating  with  water.  This  body  undoubtedly  is  the  same  as  that 
designated  Avenine  by  Johnston  and  Norton,  who  extracted  oats 
with  dilute  ammonia-water.     Analysis  VII. 

8.  When  ground  oats  are  extracted  with  10-percent-sodium- 
chloride-solution  heated  to  65°  C.  a  proteid  separates  on  cooling, 
in  the  form  of  spheroids.  This  substance  differs  in  composition 
and  properties  from  that  obtained  by  cold  salt-extraction  as  well 
as  -from  all  proteids  hitherto  described.  It  is  soluble  in  pure 
water,  precipitated  from  such  solutions  by  a  little  sodium  chloride, 
is  again  dissolved  by  a  certain  additional  quantity  and  is  precipi- 
tated completely  by  saturation  with  this  salt.  In  the  presence  of 
a  little  sodium  chloride  and  acetic  acid  it  is  soluble  in  alcohol 
of  0.9  sp.  gr.  From  solutions  in  distilled  water,  as  well  as  from 
those  in  sodium  chloride  brine,  it  has  been  obtained  crystallized 
in  regular  octahedrons.     Analysis  (of  spheroids)  VIII. 

9.  The  aqueous  extract  of  ground  oats  was  found,  in  agreement 
with  Norton  and  Kreusler,  to  contain  very  little  proteid  sub- 
stance. The  proteids  thus  dissolved  appear  to  be,  first,  a  Globulin 
similar  in  reactions  to  that  extracted  by  10-per  cent-salt-solution, 
second,  a  Proteose,  and  possibly,  third,  a  little  Acid-albumin. 
No  true  albumin  was  found  in  the  water-extract. 

10.  In  the  salt-extract  a  very  small  amount  of  a  body  was  found, 
having  the  reactions  of  Albumin,  but  not  analyzed. 

The  numbers  over  the  analyses  in  the  following  table  correspond 
with  those  of  the  paragraphs  in  the  foregoing  text. 

Composition  of  the   Proteids   from  the  Oat-Kernel. 

Analyses  by  Dr.  Thomas  B.  Osborne. 


I. 

II. 

IV. 

V. 

V.  a. 

VI. 

VII. 

VIII. 

Carbon 

53.06 

53.70 

52.33 

52.45 

52.48 

52.61 

53.49 

52.22 

Hydrogen  . 

..      6.94 

7.00 

7.19 

6.94 

6.94 

6.92 

7.01 

6.98 

Nitrogen  __ 

_.    16.38 

15.71 

16.95 

16.63 

16.85 

16.99 

16.33 

17.85 

Sulphur 

..     2.26 

1.76 

.88 

.81 

.57 

.89 

.98 

.77 

Oxygen  

._   21.38 
100.00 

21.83 
100.00 

22.65 
100.00 

23.19 

22.12 

22.59 

22.19 
100.00 

22.18 

100.00 

100.00 

100.00 

100.00 

Full  details  of  this  investigation  will  appear  in  the  forthcoming 
Annual  Report  of  this  Station  for  1890. 


Milk   Testing. 

The  attention  of  dairymen  is  called  to  a  method  of  determin- 
ing fat  in  milk  devised  by  Dr.  Babcock  of  the  Wisconsin  Station. 
Its  merits  are  that  it  is  rapid,  that  both  the  milk  and  the  fat  are 
measured  so  that  all  weighing  is  dispensed  with  and  that  it  is 
very  accurate.  It  furnishes,  we  believe,  the  most  rapid  and 
accurate  means  of  testing  milk  of  individual  cows  or  herds. 

The  apparatus  is  in  daily  use  at  this  Station.  Twenty-three 
cows  are  under  experiment  and  separate  fat  determinations  are 
made  daily  in  the  morning-  and  night-milk  of  each  cow,  the  whole, 
including  the  cleaning  of  the  apparatus,  being  accomplished  in 
two  hours  by  two  persons.  A  considerable  saving  of  time  will 
be  secured  when  power  is  used  for  driving  the  centrifuge.  With 
this  aid  a  young  man  or  woman  could  probably  do  the  whole 
easily  in  from  three  to  four  hours. 

The  Station  will  exhibit  the  working  of  the  method  at  any 
time  to  dairymen  who  desire  it  and  will  give  practical  instruction 
in  its  use. 


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